Case Analysis of Hard Anodizing Dissolution

An aerospace product bushing part, the material is LD10, the part is a tubular structure as a whole, the length is 174mm, the inner diameter is 25.5mm, the outer diameter is up to 30mm, the maximum wall thickness of the part is 2.25mm, and the thinnest part is 2mm. Concentration used in production Sulfuric acid solution adopts constant pressure method for hard anodization, the highest voltage of the film growth process is 60~70v, the bath temperature is controlled at about -5°C, the parts are mounted vertically, and the hard anodization tank is stirred by compressed air at the bottom .

3.1 Reason analysis of materials and process parameters For this part, because LD0 material is also used in other products, and the fixed program used in the hard oxidation process, process parameters and boost curves are automatically carried out by the power supply device. There is no problem with the parts of ID10 material, indicating that the final voltage selected for LD10 material is 60~70V, and there is no problem with the boost process in the hard oxidation process. It should be reasonable. Therefore, the boost for LD10 material and hard oxidation process There is no problem with the speed, which is not the reason for the dissolution of the parts. 32 Analysis of the uneven current density phenomenon. According to the actual parts where the parts are dissolved, the film layer of the parts at the fixture mounting position is intact, and there is no dissolution phenomenon.